The proposed work is designed to elucidate RNA metabolism as it is related to growth, development and function, both of individual cells and the organism. The enzyme which catalyzes the synthesis of RNA, DNA dependent RNA polymerase (ribonucleoside triphosphate: RNA nucleotidyltransferase EC 2.7.7.6) will be further purified and the properties of the enzyme will be investigated using enzymes and chromatin and DNA of various normal and neoplastic tissue. RNA polymerase activity in viruses and virus-infected cells will also be studied. It is anticipated that these studies will result in an insight not only into the normal regulation of RNA synthesis but also into the nature of certain disease processes, notably neoplastic transformation.